Lifting gear, for example, front loaders, are attached to vehicles and are used for lifting and transporting loads. They are provided with hydraulic cylinders for the lifting of the load, and as a rule, also for the pivoting of the load, which are supplied with pressurized hydraulic fluid from a carrier vehicle through removable, flexible hoses. In order to prevent the load from falling down in the case of a broken hose that leads to a fall-off of the pressure in the cylinder holding the load, so-called load retaining or safety valves are used. These valves block the connection between the cylinder and the hose as long as the operator does not initiate any movement of the lifting gear.
Furthermore, it is possible to connect the hydraulic cylinders of the lifting gear with pressure accumulators acting as vibration dampers that are provided on the lifting or lowering side of a cylinder or on both sides (DE 197 34 658 A). Such pressure accumulators are connected at the connecting point on the vehicle side of the safety valves, since as a rule, they are located on the vehicle and are connected by a hose with the safety valve. In order to obtain damping even when the safety valve is turned off, the operator can manually deactivate the safety valve. The operator then assumes the responsibility of not performing any lifting operation. It is also conceivable that the safety valve can be activated as a function of the speed of the vehicle. If the vehicle is operated at a certain speed, a conclusion can be drawn that the vehicle is not operated in a lifting condition, but in a transport condition. Then the pressure accumulator is effective only during the transport operation.
The problem underlying the invention is seen in the need to improve a load lifting arrangement with a safety valve in such a way that a damping of the cylinder is possible, even if the safety valve is turned off or that the safety valve remains effective even with a damped cylinder.